Four-way reversing valve compressure difference control method of multi heat pump system

摘要

PURPOSE: A method for controlling a four-way valve of a multi-type heat pump system is provided to generate a pressure difference between a suction pipe and an exhaust pipe of a four-way valve by gradually increasing the rotation speed of a fan. CONSTITUTION: A method for controlling a four-way valve of a multi-type heat pump system is as follows. When a heating mode is selected, a first compressor is driven(S14). It is confirmed whether the area is a cold district or not. If the area is the cold district, a first indoor unit and a second indoor unit are successively operated. When the first and second indoor units are operated, a second compressor is driven(S24). When the second compressor is driven, a refrigerant discharged from the second compressor is supplied to the first and second indoor units(S30).